Another possibly useful bit of code that creates QR codes in SVG format:

This depends on netpbm and qrencode. Basically, what we do is create a QR code PNG, convert it to a PBM text file, and mangle that with an awk script (an admittedly naive script, but it should work for addresses and private keys) into an SVG file.

You can then merge these with one of the SVG note designs already given however you want. I'm thinking a little HTML file with some CSS positioning info should work to overlay QR codes (and, optionally, text) over a note. By keeping all images in SVG format, your notes should print at whatever resolution your printer can deliver.

Next time I revisit this image, it needs to have some color bleeds so that minor variations in cutting don't result in white stripes along the edges.

If someone else beats me to it, please add bleeds.

Companies claiming they got hacked and lost your coins sounds like fraud so perfect it could be called fashionable. I never believe them. If I ever experience the misfortune of a real intrusion, I declare I have been honest about the way I have managed the keys in Casascius Coins. I maintain no ability to recover or reproduce the keys, not even under limitless duress or total intrusion. Remember that trusting strangers with your coins without any recourse is, as a matter of principle, not a best practice. Don't keep coins online. Use paper wallets instead.

Notes are rendered four to a page. Five denominations (0.5,1, 2, 5, and 10 BTC) are currently supported, each of which prints in its own color. Addresses and private keys are generated on-the-fly, rendered as both text and QR codes. Page layout is done in PostScript with artwork that started out as SVG, so you get the highest print quality possible. For convenience, final output is to PDF. I considered using HTML and CSS to position SVG images directly, but print quality proved a bit hit-or-miss...Firefox was usually OK, but Chrome frequently rendered SVG elements at 72 dpi or so before printing. Even with Firefox, I sometimes had some unexplained print failures.

Notes are rendered four to a page. Five denominations (0.5,1, 2, 5, and 10 BTC) are currently supported, each of which prints in its own color. Addresses and private keys are generated on-the-fly, rendered as both text and QR codes. Page layout is done in PostScript with artwork that started out as SVG, so you get the highest print quality possible. For convenience, final output is to PDF. I considered using HTML and CSS to position SVG images directly, but print quality proved a bit hit-or-miss...Firefox was usually OK, but Chrome frequently rendered SVG elements at 72 dpi or so before printing. Even with Firefox, I sometimes had some unexplained print failures.

point me to a link that generates those with a unique private key... (wallet)

If you're referring to my project, you need to clone it from the GitHub repo, make sure you have the software (including vanitygen) listed under Prerequisites in the README, and run the script. Each run generates new privkeys for each note. It's intended for offline use; it's not offered as a web service.

It now produces 3/4" squares with human-readable privkeys that can be placed over the privkey QR codes before applying your tamper-evident labels. Black boxes are also generated on the back opposite the privkey QR codes; if nothing else, they'll help you line up the label on the back.

What do you mean "Printer manufacturers are controlled by reptilians"? Is it actually insecure to print something sensitive, then connect the printer to an internet-connected machine? Even when power cycling it?

If one computer is used to hash the passphrase, and you transfer the hashed version of it to another computer to produce the notes (via the "intermediate generator"), it would require a compromise of both machines for anyone to be able to decrypt the notes.

Companies claiming they got hacked and lost your coins sounds like fraud so perfect it could be called fashionable. I never believe them. If I ever experience the misfortune of a real intrusion, I declare I have been honest about the way I have managed the keys in Casascius Coins. I maintain no ability to recover or reproduce the keys, not even under limitless duress or total intrusion. Remember that trusting strangers with your coins without any recourse is, as a matter of principle, not a best practice. Don't keep coins online. Use paper wallets instead.

My understanding is it can be compiled for Mono (probably only if you're into compiling stuff yourself, this won't be point-and-click). And it certainly runs under Windows using Parallels, Bootcamp, or any solution allowing Windows itself to run on a Mac.

Companies claiming they got hacked and lost your coins sounds like fraud so perfect it could be called fashionable. I never believe them. If I ever experience the misfortune of a real intrusion, I declare I have been honest about the way I have managed the keys in Casascius Coins. I maintain no ability to recover or reproduce the keys, not even under limitless duress or total intrusion. Remember that trusting strangers with your coins without any recourse is, as a matter of principle, not a best practice. Don't keep coins online. Use paper wallets instead.

The back pattern has been rotated 90 degrees so the URLs show up better on the finished notes. Next update will more than likely add more denominations (at least BTC0.1 and BTC0.2, and maybe some bigger notes) in more colors.